There's something about Morstan
by Ariane DeVere
Summary: John clearly fell for the young woman the moment she arrived at the flat, and the feeling is obviously mutual.  But why does Sherlock find himself positively approving of the budding relationship?  He investigates ... and learns the terrifying truth.


**There's something about Morstan**

The young blonde woman smiled winningly at John, who gazed adoringly back at her. Clearly he had fallen for her the moment she walked into the flat seeking a consultation with Sherlock, and the attraction was obviously mutual.

Since she had sat down and begun to explain her circumstances, John's gaze hadn't left her for a second, which Sherlock found rather irritating. Usually when a client visited, John was his wing man, sitting beside him and taking notes, checking information for him on the laptop and generally acting as his personal secretary. But almost as soon as Miss Morstan had entered the flat, John's attention had been totally upon her and he had pulled one of the dining table chairs across the room so that he could sit beside her as she sat in his armchair. He hadn't even offered to make her a cup of tea, apparently reluctant to leave her side and go to the kitchen from where he wouldn't be able to see her face.

Mary didn't seem to mind the attention, however; in fact she was positively _simpering_ under his gaze and batting her eyelashes flirtatiously at him. If any other woman had been so obvious while looking at John, Sherlock would have rolled his eyes and would probably have made some sarcastic remark by now, but the two of them looked so delightful together that any spiteful comments that rose in his mind immediately receded before he could even open his mouth. But nevertheless, they were gazing at each other and not at him, and that just wasn't on.

Sherlock sighed noisily and after a long moment they both reluctantly turned their attention back towards him where it belonged.

As Mary's eyes met his, Sherlock's heart instantly melted. She really was rather adorable and his immediate instinct was to trust her even though he didn't understand why. He had _never_ trusted anyone at first glance like this – well, only Joh... Oh! He remembered how, as soon as John had limped into the lab at Bart's, a voice in his head had started repeating an unusual word which – while it made no sense – had prompted him to believe that he should trust this man. He had tried to ignore the voice but it had persisted and, despite himself, he had taken an instant liking to the Army veteran and had believed that he would be the ideal flatmate. Just _how_ ideal had only been proven later but he had never felt that immediate level of trust for anybody before or since that moment. So it was strange to have that voice back in his head now – a voice which he had never heard in real life – speaking up again and inferring that he could place that same level of trust in this young woman. Even more disturbing was the method the voice was using to tell him this: it made no sense that Sherlock should know so instinctively that John, and now Mary, were going to be an important and vital part of his life simply because an unrecognisable voice was repeatedly murmuring inside his brain, '_Canon, canon, canon_ ...'

A little worried by the way that he kept finding himself wanting to smile genuinely at her instead of producing his normal forced grimace, and even more disturbed by how _not_ disturbed he was at the obvious instant attraction between John and Mary, he tried to distract himself by turning to his laptop on the desk beside him and – making sure that she couldn't see the screen – starting to research the delightful Miss Morstan online. Ignoring the easier option of getting into police files and instead hacking straight into Mycroft's security servers, he pulled up as much information as he could about her, peripherally aware of how comfortably Mary and John were chatting nearby and finding himself smiling at hearing John's easy laugh. At this rate, Sherlock wouldn't be surprised if they were engaged within months, and even the thought of John moving out of 221B wasn't distressing him as much as he would have expected. After all, Mary was _so_ delightful and sweet. And even while he tried to be concerned about his strange reaction to her, the voice in his head kept reassuring him: '_Canon, canon, canon_ ...'

He was relieved to see from the security files that Mary wasn't some arch-villain masquerading as the private tutor which she claimed to be. She really did work as a home tutor; her references all told what a lovely woman she was and how her employers' children adored her; she was twenty-seven years old (_far_ too young for John ...) ('_Canon_ ...') (... well, no, just because she was ten years younger than him, it would still be a marriage made in heaven); her friends and colleagues all checked out and had no trace of criminal histories; her father really _had_ disappeared in mysterious circumstances ten years ago (Sherlock marvelled at how lucky the world was that the lovely Mary hadn't fallen apart under the strain of such a loss); she had now received a letter promising to reveal the mystery of Captain Morstan's disappearance; ... and her full name was ...

No. Oh, _no_. It _couldn't_ be.

Sherlock stumbled to his feet, shocked. Mary turned her wonderful smile towards him ('_Canon, canon_ ...' whispered the voice in his head) and Sherlock felt instantly reassured. She was far too lovely and trustworthy – she couldn't _possibly_ be the hideous person he had just seen on his computer screen.

'_Canon_ ...' the voice continued to whisper.

"Shut _up_!" he said out loud and now John's eyes flickered briefly in his direction. Sherlock reluctantly dragged his eyes away from the adorable woman sitting beside his flatmate and looked at the computer screen again, forcing himself to confront the truth. Almost snarling with the effort, he turned his head towards her again but kept his eyes averted.

"Get out," he said sternly.

John, who was continuing to gaze devotedly at Mary as if planning their wedding and wondering what the chances were that they could book the church a week next Tuesday, frowned in confusion but still seemed unable to look away.

"Sherlock, don't be silly," he told his friend. "We're not going anywhere."

Sherlock grimaced and forced his voice to sound harsh as he addressed Mary.

"I know who you are," he told her, struggling to resist the urge to cringe and apologise as she blinked at him innocently.

"Mr. Holmes, I don't know what you mean," she said sweetly.

Sherlock gestured towards his computer. "It's all here," he told her angrily. "I know everything about you – and I _know your name_."

And then the world went to hell.

Mary rose to her feet, her entire demeanour changing as she faced Sherlock. Her eyes widened and her voice morphed from the gentle tones it had produced up until now and became shrill and hysterical.

"You can't throw me out!" she told him. "I love you! And him!" She gestured wildly towards John. "I'm going to marry him, and you're going to love me too and we're all going to live together and have babies, and the flat will be full of puppies and kittens and jam and we'll look after baby hedgehogs and live happily ever after!"

John stood up and backed away from her as she continued to rant. She began to flail her arms about as she turned to him. "You _have_ to marry me, John! We're destined to be together! It's in the books and everything!"

"The books ...?" John asked in apparent confusion, clearly trying to come to terms with the dramatic change in his future wife.

"Mrs Mary Watson," she said, her voice quietening down for a moment and becoming dreamy. She smiled, her gaze distant and fanatical. "Mrs Mary Watson-Holmes," she added more loudly, grinning manically.

"Get out," Sherlock told her again, pointing towards the door for added emphasis.

"You don't understand!" she told him wildly. "It's our destiny!" She looked at John again. "You _have_ to love me! It's in the books; it's on the DVDs of all the old television series; it's in the films! It's ... it's ..."

"... _canon_," Sherlock finished grimly.

Mary squealed delightedly. "Yes! You _do_ understand! I knew you would!"

"Out," he said again, his finger pointing firmly towards the door.

John's face was full of bewildered misery but he seemed to take his cue from the friend he had trusted for so long and reached out a hand towards Mary.

"I think you had better leave ..." he began but she shrieked excitedly the moment his fingers touched her arm.

"You touched me!" she squealed. "You _do_ love me!"

John snatched his hand back, his eyes beginning to fill with panic as she gazed at him adoringly.

"Sod this," Sherlock said in irritation and took his phone from his jacket pocket. Hitting a speed dial, he waited impatiently for a reply and began speaking as soon as the phone at the other end was picked up.

"Lestrade, we've got an intruder in the flat," he said. "We need police assistance."

He started to listen to Lestrade's reply but snapped out his answer before the inspector had finished speaking. "No, we _can't_ throw her out of the window. We daren't touch her."

"It's a woman?" Lestrade asked.

"Yes, well done for deducing that," Sherlock said tetchily. "She's hysterical and will get even worse if we try to manhandle her out. Come over here and remove her for us."

Mary's eyes glazed and her grin became wider. "The silver fox," she said dreamily.

Sherlock growled. "No, don't come yourself," he said urgently into the phone. "Send ..." he paused and looked at Mary cautiously, then added hesitantly, "... Dimmock?"

Her smile faltered momentarily but then strengthened again. "He's really sweet," she said with a look of adoration on her face.

"No, not Dimmock," Sherlock instantly said into the phone. He hesitated, then was struck with an inspiration. "Send _Anderson_."

Mary's eyes began to fill with panic. "You wouldn't," she said nervously.

"Anderson isn't trained to remove intruders," Lestrade's voice said down the phone. Sherlock ignored him.

"Send Anderson," he insisted, then grinned savagely. "And _Donovan_."

Mary let out an anguished sob.

"Anderson and Donovan," Sherlock said again. "And _no-one_ else. For God's sake don't send Hopkins or we'll _never_ get rid of her."

Switching the phone off before Lestrade could reply, he turned towards the sobbing woman. "You've got two minutes before they arrive," he told her. "Donovan and _Anderson_."

"I'm going," she said tremulously, turning towards the door. Then she turned back, the fanatical glint back in her eyes. "Can I stroke the Coat before I go?"

"_OUT_!" Sherlock and John said simultaneously.

Pouting petulantly, the formerly lovely and adorable Miss Morstan slunk out of the room and clumped off down the stairs. Once the front door had slammed noisily, John sank down into his chair, blowing out a shaky breath, and looked up at his friend.

"What the bloody hell was all _that_ about?" he demanded.

Sherlock had regained his composure and sat back down at the table, looking at his flatmate smugly. "Ah, John, as usual you do not observe," he told him serenely.

He gestured to the screen on his laptop.

"It doesn't matter how appealing such a woman might seem at first – you should never trust someone called Mary."

He paused dramatically for a moment, then delivered the dénouement.

"_Especially_ if her middle name is Sue."

* * *

><p><span>Author's Note<span>: All right, I'll do it for you. For those of you who read the ending and went, "... the _hell_ is she on about now?" here's an extract from the Wikipedia definition:

_A Mary Sue, in literary criticism and particularly in fanfiction, is a fictional character with overly idealized and hackneyed mannerisms, lacking noteworthy flaws, and primarily functioning as a wish-fulfilment fantasy for the author or reader. "Mary Sue" is commonly associated with self-insertion (the writing of oneself into a fictional story). "Mary Sue" always gets her man; the "right people" seem to gravitate towards the character._

I really must stop writing stories that need acres of explanation afterwards!

But does this story imply that _I'm_ a Mary Sue?

Umm ... no? No, _definitely_ not – I would never behave like that if I met Sherlock and John in real life. *nods convincingly* (Well, not that I would admit in public anyway.)

Oh, and the reference to Hopkins might go over the heads of anyone who hasn't read **verityburns**' "The Green Blade". Just trust me on this: he's cute.


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